Brain-computer interface (BCI) research seeks to give people with severe motor disabilities (e.g. amyotrophic lateral sclerosis, brainstem stroke, cerebral palsy, and spinal cord injury) communication and control technology that does not depend on neuromuscular output. BCI can provide people who are severely disabled with non-muscular methods for controlling cursor movements, selecting letters or icons, or even operating neuro-prostheses. Facilitated and encouraged by new understanding of brain function, by the advent of powerful low-cost computers, and by appreciation of the needs and potentials of people with disabilities, BCI research has grown rapidly through the past decade and its growth has greatly accelerated in the past two years. Effective BCI research requires interdisciplinary interactions involving neuroscience, psychology, engineering, mathematics, computer science, and clinical rehabilitation. No standard venue brings these groups together, in recognition of this, and of the growth in BCI research, the NIH sponsored and the Wadsworth Center organized in 1999 and 2002 the first two international BCI meetings. These meetings brought together researchers from all over the world and included all relevant disciplines. Foundation support allowed many graduate students and post-doctoral fellows to participate. The meetings were extremely successful. The first was reported in 18 peer-reviewed papers in a special section of IEEE Trans. Rehab. Eng, and the second in 28 peer-reviewed papers in a dedicated issue of IEEE Trans Neur. Syst. Rehab. Eng. In large part due to the interdisciplinary interactions fostered by these meetings, BCI research continues to grow even more rapidly. This proposal seeks core funding for the Third International BCI Meeting, June 14-19, 2005. The mornings of the first three days will provide concise updates from about 50 BCI laboratories, and the afternoons will be devoted to four parallel workshops addressing the four critical areas of BCI research: signals and recording methods; signal processing; clinical issues and applications; and software and hardware. The fourth day will be a plenary session comprised of summary presentations from each workshop. Evenings will offer a keynote address, poster sessions, and BCI demonstrations. Foundation support contingent on the success of this proposal will fund students and fellows. Proceedings will be published as a dedicated issue of IEEE Trans Neur. Syst. Rehab. Eng. By bringing together essentially all active BCI research groups, by focusing on the most important issues, by involving students and fellows, and by producing a comprehensive state-of-the-art set of papers, this Third International BCI Meeting should greatly encourage and facilitate continued BCI research and development.